Calculating device.



No-. '745,586. PATENTED DEC. 1, 1903 T. FINIGAN & E.'P. W. WIEDA.

v CALCULATING DEVICE.

APPLICATION FILED JAN. 19, 1903:

NO MODEL.

\(WITNESSESW INVENTORS 2mm 9%W67%.#%

ATTORNEYS.

UNITE STATES Patented December 1, 1903.

PATENT OFFICE.

THOMAS FINIGAN AND ERNST F. W. VVIEDA, OF PATERSON, NEXV JERSEY.

CALCULATING DEVlCE.

5IPECIFICATION forming part of Letters Patent No. 745,586, datedDecember 1, 1903.

Application filed January 19,1903. SerialNm139A98. (No model-3 T0 aZZwhom it may concern.-

Be it known that we, THOMAS FINIGAN and ERNST F. W. WIEDA, citizens ofthe United States, residing in Paterson, in the county of Passaic andState of New Jersey, have invented certain new and useful Improvementsin Calculating Devices; and we do hereby declare the following to be afull, clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and to lettersof reference marked thereon, which form a part of this specification.

Our invention relates to calculating devices; and it consists in animproved device of this nature adapted particularly for adding andsubtracting.

Ourinvention willbe found fullyillustrated in the accompanying drawings,wherein- Fi ure 1 is a plan view showing that side of the device onwhich the subtracting is effected. Fig. 2 is also a plan view, butshowing that side of the device on which the adding is done; and Fig. 3is a side or edge view of the device.

The essential feature of our invention consists in providing each of twoparts, one of which is arranged to rotate on the other, with a series ofnumbers, begininng with naught, so arranged that by bringing the twoseries into a given 16l2tl3lOl1-?:.., so as to add or subtract any twonumbers which may be comprised within the series-an indicator or indexon one of the parts will designate the re sult on another series ofnumbers on the other part.

In the drawings, a is a base or body part of cardboard or other suitablematerial, while I) and c are two disks which have a common pivot on arivet (1 extending through parts a, b, and c, the said disks being eachpreferably disposed between Washers c on the rivet.

Referring first to that portion of the device whereby subtracting iseffected, base CL and disk 6 have each a series of numbers f g, runningfrom naught to ninety-nine and disposed concentrically close to theperiphery of disk 1). Under disk I) is arranged another series 7?. ofnumbers, this series likewise running from naught to ninety-nine andbeing disposed close tothe periphery of disk I). When the two naughts ofthe series of numbersf and g register, an opening 1,, which serves as anindex, uncovers or discloses zero on the series of numbers it. It shouldbe remarked that the several series of numbers run in the samedirection. The series of numbers f are the subtrahend-numbers, theseries of numbers g the minuend-numbers, and the numbers 7b theresult-numbers. Now upon a View to Fig. 1 it will be seen that with theparts disposed as there shown the subtracting of any number on disk 6from its neighbor on disk CtWlll be the result shown at the index, O.With this understood it will not be diflicult to see that if disk b ismoved one, eight, or any other number of points, so a correspondingnumber will show at the index. So that, suppose it were desired tosubtract five from eight, since that would require moving disk?) threepoints, 3 would be shown by the index, and of course the same would bethe result if six were subtracted from nine, nine from twelve, and soon.

Referring now to that portion of the device whereby adding is effected,on the base a and disk 0 are inscribed. reverse concentric series ofnumbers j 713, respectively. The se ries j is disposed just inside of acircle Z on base a, while the series in is disposed just inside asemicircular indentation min the disk 0. Outside of and concentric withthe circle 1 is another series of numbers or, running from naught toninety-nine. On disk 0 is a pointer 0, serving as an index for theseries of numbers it. On account of the reverse arrangement of series ofnumbersj and 7c the sum of any two coinciding numbers, one from each ofthese series, will be the same as the sum of any other two. Now if diskcis turned in the direction of the arrow, say, one point each number inseries will be brought opposite the number in seriesj, which is onehigher than that at the previous position of disk 0. Thus supposing theparts are arranged as in Fig. 2 and it is desired to add fifty and oneor forty-seven and four or thin teen and thirty-eight, this will mean toadvance the disk one point with the consequence that the pointer o isbrought opposite 51, a number which is higher by one than the previousnumber to which it pointed. If it is desired to add, say, fifty andthree or any two numbers having that corresponding relation at thestart, the required movement of the disk three points will show 53 inthe series n, and so on.

In order to facilitate turning the disks, a thin metallic plate 19,having securing-spurs q, is attached against the outer surface of eachdisk, the plate being dished, as at 4', to receive the end of theoperators finger.

Having thus fully described our invention, What We claim as new anddesire to secure by Letters Patent, is-

1. The combination of two members pivotally secured together andprovided the one With two and the other With a single series of numbers,said series being concentric and all of them being adapted to beemployed in performing each calculation, and an index forming a part ofthe member having the sin-

